Tachometer.



Nn. 687,650. Patented Nov. 26, 19m.

. E. PLACE.

TACHOMETEB.

(Application led Dec. 31, 1900.) (No Mudgl.) v 2 Sheets-Sheei I.

lll/111111 No. 687,650. Patented Nav., ze, mol.

E. PLACE. TAcHomETEa.

` {Application led Dec. 31, 1900.) A (No Model.) l 2 Sheets-sheet 2.

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77765505 s QM M; m

NITED STATES lUirnNT Fries.

EDWIN PLACE, OF SCHENECTADY, NEW YORK.

TACHOMEEl-i.

SPECIFICATION forming part of Lettere Patent ne. 687,650, dated November2e, 19061.

Application filed December 31, 1900. Serial No. 41,624. (No model.)

To` all whom it may concern:

` Be it known that I, EDWIN PLACE, a citizen l of the nited States,residing at Schenectady, county of Schenectady, and State of New York,have invented certain new and useful Improvements in Tachometers, ofwhich the following is a specification.

The invention relates to such improvements; and it consists of the novelconstruction and combination of parts hereinafter described andsubsequently claimed.

Reference may be had to the accompanying drawings, and the referencecharacters marked thereon, which form a par't of this specification.

Similar characters refer to similar parts in the several gures.

Figure l of the drawings is a view in front elevation, partly insection, of my improved tachometer. Fig. 2 is a View of the same, partlyin central vertical section, on the broken line`2 2 in Fig. l, andpartly in ele- Vation. Fig. 3 is a view infront elevation 'of thecylindrical gear-case. Fig. 4 is a view of the gear-rack and spindlebroken away at both ends. the gear-case on the broken line 5 5 in Fig.3. Fig. 6 is a view in side elevation of the same. Fig. 7 is a view infront elevation of a broken-away portion of the tubular inclojsure forthe gear-rack, showing the gear-case in front elevation. Fig. 8 is adetail view, part-ly in section, showing the stepped bearing for theinner end of the shaft for operating the centrifugal mechanism andconnections between said shaft, centrifugal mechanism, and spindleoperated thereby. Fig. 9 is a view of the same, partly in vertical`cross-section, on the broken line 9 9 in Fig. 8. Fig. 10 is a view inhorizontal cross-sec,-

tion, taken on the broken line 10 10 in Fig.

Fig. 5 is a horizontal section of Referring to the drawings, the case ofthe instrument comprises two parts 1 and 2, one containing a chamber forthe centrifugal mechanism and the other a chamber for the 'gearmechanism, which operates the index. The shaft 3 extends axially throughthe chamber formed by the inclosure 1, being provided withbearing-supports in the'end walls of the inclosure adapted to permit arotative movement of said shaft, and the bearing-support for the innerend of said shaft being in the form of a stepped bearing, as shown atet, adapted to resist an inward thrust of said shaft. The outer end ofsaid shaft projects through the end wall of the inclosure and isprovided with an outer shaft member 5,capa ble of endwise movementthereupon, the coilspring 6 being interposed between said shaft members,as shown in Fig. 1. The outer member 5 is provided with anangularlypointed outer end 7, adapted to fit a similarlyformed recess ina rotating object, as in the end of a shaft, (not shown,) in the usualmanner to cause the rotary movements of said object to be transmitted tothe tachometer'shaft. By interposing the spring 6 between the shaftmembers I am able to force the pointed end of the outer memberagainstthe rotating object with considerable force without subjectingthe stepped bearing at the inner end of the tachometer-shaft to unduefriction and wear, such as to interfere withV the uniformity of itsoperation and the accuracy of the instrument. The inclosure 1 alsocontains the centrifugal mechanism, which comprises4 the spring-plate 8,having its ends secured at 9 to a boss 10, xed upon the shaft 3, and itsmiddle portion bowed and provided with a slot 11, adapted to receive andfit and move upon the Vinner flattened portion 12 of the shaft 3.v Thearms of the bowed spring-plate maybe provided with weights 13 in anyknown form. Rotary movements imparted to the shaft 3 will thus causerevoluble movements of said weights, and centrifugal force will causethe outward movement of said weights and a iattening movement of saidbowed spring varying in accordance with the speed of the moving parts.

The centrifugal mechanism may be caused to operate an index in any knownmanner. I have shown a spindle 14, extending axially IOO of pins orrivets 18.

througha tubularinclosure 15, located within the inclosure 2, the lowerend of said spindle projecting through a central aperture 16, formed inthe step bearing-block 17, secured upon the upper end of the flattenedportion of t-he shaft 3, which is preferably bifurcated, as shown, thebifurcate ends being secured in recesses in the bearing-block 17 bymeans The bearing-block 17 forms practically the end of the shaft 3, andthe shaft is thus provided with an axial end aperture 16, and thetransverse slot 19 between the bifurcate arms intersecting said axialaperture. The end of the spindle 14 which projects down through thecentral aperture 16 is provided with a transverse aperture 20, throughwhich a wire link 21 is passed f and extended out through the transverseslot 19, having its ends introverted to embrace the side edges of thespring-plate, as shown in Fig. 9, thus connecting said plate and spindlewithout weakening the spring or interfering with the movement of eitherpart. The spindle-shaft 3 and centrifugal mechanism are thus connectedto rotate in unison, while the movements of the bowed portion of thespring due to variations in centrifugal force will cause reciprocatingmovements of the connected spindle 14, which may be caused to operate anindex in any known manner.

The spindle 14 is preferably provided with an annular toothed gear-rack31, adapted to operate the index by suitable gear connections. As ameans for supporting such mechanism I provide a cylindrical gear-case21, adapted to be inserted transversely through apertures in thecylindrical inclosure 15 and frictionally held therein. This gear-caseis preferably provided with oppositely-located slots 22, which permitthe cylinder to be compressed or contracted while being inserted inapertures in the inclosure 15, slightly smaller than the diameter of thegear-case, the resilient expansive force of the case-wall beingsufficient to securely hold it in place. Said slots 22 are locateddiametrically opposite each other and permit the spindle 14 to passdiametrically through the gear-case. Portions of the gear-case wall arecut and bent inwardly to form bearing-supports 23 and 24 for the innerends of the axially-arranged index-shaft 25 and pinion-shaft 26,parallel with the axis of said case and eccentric thereto. Outerbearing-supports for said shafts 25 and 26 are formed in the I-plate 27,which extends transversely of the front end of the case and isfrictionally held in slots 28, formed in the front end of the case-wall.The pinion 29 is fixed upon the shaft 26 in position to mesh with apinion 30, fixed upon the index-shaft, and also to be engaged by agear-rack 31, comprising a series of annular teeth on that portion ofthe spindle 14 which passes through the gear-case. The reciprocatingmovements of the spindle induced by its connection with the centrifugalmechanism will thus cause operation of the index 33,

fixed upon the shaft 25 and adapted to rotate in proximity to a dial 34,fixed upon the inclosure 2 and covered, if desired, by a glass 35.

By having the gear-rack 31 extend diametrically through the gear-caseand the pinion 29 supported eccentrically in said case I am able by aslight rotary adjusting movement of the frictionally-held case to forcethe pinion 29 into more or less close mesh with the gear-rack to take uplost motion and compensate for wear, and this without disturbing theaxial position of the index shaft. To permit of such rotaryadjustingmovement of the gear-case, the slots 22 are made of a width somewhatgreater than the diameter of the gearrack.

If desired, the spindle 14 may be provided with a piston 36, located ina cylindrical chamber 37, formed in the tubular inclosure 15 by thediaphragms 38, thereby forming a dashpot construction, which serves as abrake to prevent a too-sudden movement of the operating parts.

What I claim as new, and desire to secure by Letters Patent, is

1. In a tachometer, or the like, the combination with a shaft having aflattened portion; and means for rotatively supporting said shaft inoperative connection with a rotating object; of centrifugal mechanismconnected with said shaft and comprising in part a spring plate havingits middle portion bowed and providedwith a slot adapted to receive andtit the flattened portion of said shaft and move thereon as the rotaryspeed of said shaft varies; and an indicator connected with saidcentrifugal mechanism.

2. In a tachometer, or the like, the combination with a shaft rotativelysupported by bearings at or near its opposite ends and having in one endan axial aperture and near said end a transverse slot intersecting suchaxial aperture; and means for supporting said shaft in operativeconnection with a rotating object; of centrifugal mechanism connectedwith said shaft; an indicator; a spindle operatively connected with saidindicator and having its end located within the apertured end of saidshaft; and mechanism ex= tending through the transverse slot in saidshaft and connecting said spindle with said centrifugal mechanism.-

3. In a tachometer, or the like, the combination with a shaft having aflattened portion, an axial aperture in one end and a transverse slot inits attened portion intersecting said axial aperture; means forrotatively supporting said shaft in operative connection with a rotatingobject; and centrifugal mechanism connected with said shaf t comprisingin part a spring-plate having its middle portion bowed and provided witha slot adapted to receive and fit the flattened portion of said shaftand move thereon as the rotary speed of said shaft varies; an indicator;a spindle operatively connected with said indicator and having atransverselyapertured end located within IIO I 3ro the apertured end ofsaid shaft; and a link passed through the transverse aperture in saidspindle and slot in said shaft with its ends embracing the side edges ofsaid springplate, substantially as described.

4. In a tachometer, or the like, the combination with a shaft having anaxial end aperture; means for rotatively supporting said shaft inoperative connection with a rotating obj ect; and centrifugal mechanismconnected with said shaft; of an endWise-movable spindle having one endsupported and reciprocatory in said apertured end of said shaft; saidshaft and spindle being connected to rotate in unison; means forrotatively supporting the other end of said spindle; an indicator; andoperative connections between said spindle and said indicator andcentrifugal mechanism respectively, substantially as described. v

5. In a tachometer, or the like, the combination with a shaft having anaxial end aperture; means for rotatively supporting said shaft inoperative connection with a rotating object and centrifugal mechanismconnected with said shaft; of a rotary andendwise-movable spindleprovided with an annular toothed gear-rack and having one end rotativelyreciprocatory in the apertured end of said shaft and connected to rotatetherewith; means for rotatively supporting the other end of saidspindle; an indicator; gear connections between said indicator andgear-rack; and operative connections between said spindle andcentrifugal mechanism, substantially as described.

6. In a tachometer, or the like, the combination with centrifugalmechanism; means for supporting the same in connection with a rotatingobject; and a gear-rack in operative connection with said centrifugalmechanism;

of a tubular inclosure and support for said gear-rack a tubulargear-case inserted transversely through apertures in said tubularinclosure and frictionally held therein; an index-shaft and gearconnections between said shaft and gear-rack supported by said gearcase;and an index7 substantially as described.

7. In a tachometer, or the like, the combination with an index-operatinggear-rack; and a cylindrical inclosure therefor; of a slottedcylindrical gear-case inserted transversely through apertures in saidcylindrical inclosure and frictionally held therein with said rackextending diametrically through its slotted portion; a pinion meshingwith said gearn rack, and rotatively supported in said gearcase with itsaxis parallel with the axis of said case and eccentric thereto; anindex; an index-supporting shaft axial to said case; and a pinion onsaid index-shaft meshing with said eccentric pinion, substantially asdescribed.

8. In a tachometer, or the like, the combination with a rotary shaftadapted to connect with a rotating object; a supporting-case 3 andcentrifugal mechanism connected with said shaft; of a spindlereciprocatory in suitable bearings and connected with said centrifugalmechanism to be reciprocated thereby; an index; connections between saidindex and reciprocatory spindle; a dash-pot cylinder inclosing saidspindle and a piston on said spindle located within said cylinder,substantially as described.

In testimony whereof I have hereunto set my hand this 22d day ofDecember, 1900.

EDWIN PLACE.

Witnesses:

H. W. DENNINGTON, DANIEL l?. I-IALTON.

